Experimental study on mechanical properties of toothed blocks in concrete box girders with new prefabricated reinforcement parts

Abstract To meet the demands for efficient and high-precision assembly construction of steel reinforcement components in concrete structures, and to address the limitations of steel reinforcement binding methods for concrete box girder structures, two innovative types of steel reinforcement components, namely end-anchored and anchor plate types, were proposed. Their stress reliability was validated through mechanical performance tests. The results indicate that when compared to traditional tooth blocks, the newly proposed end-anchored and anchor plate tooth blocks exhibit minimal differences in their final form at the prestressed design load. Furthermore, they provide safe and reliable bearing capacity, meeting the specified requirements. The load-strain curve for traditional and anchor plate toothed blocks exhibits notable slope changes, whereas the strain in end-anchored toothed blocks consistently rises with increasing load, with their bearing capacity not yet reaching its limit. The anchor plate-type tooth block can enhance its stress-bearing capacity by strengthening the transverse load-bearing steel bar structure. The assembly speed of end-anchored type gear block and anchor plate-type gear block steel parts is fast. The installation time of end-anchored type gear block is 1/4 of that of traditional gear block, and the installation time of anchor plate-type gear block is only 1/12 of that of traditional gear block. Moreover, the bearing capacity is safe and reliable, and it can be promoted and applied in highway bridge engineering.